Question

The area of triangle with given two sides 18cm and 10cm respectively and perimeter equal to 42 cm is:​

Answer 1

Perimeter of Δ=a+b+c

42cm=18cm+10cm+c

c=(42-28)cm

c=14cm

s=(a+b+c)/2

s=(18+10+14)/2

s=42/2=21

Area of Δ=√s(s-a)(s-b)(s-c)

area of Δ=√21(21-18)(21-10)(21-14)

=√21×3×11×7

=21√11cm²

Hope it helps you buddy.........